diff --git a/modules/util/lon_lat_grid.py b/modules/util/lon_lat_grid.py
index 40274abaf43a04c18d4651891d6c0660119d8b92..cae5bcf564ffc39a8cafda11a83bdd9fb9b56df3 100644
--- a/modules/util/lon_lat_grid.py
+++ b/modules/util/lon_lat_grid.py
@@ -21,6 +21,8 @@ class LonLatGrid:
     # Incoming longitude must be in range: 0 - 360 degrees
     # Can have NaN for off Earth grid points (these are handled internally).
     # closeness_threshold (m): if < distance of located_point to target, return off grid
+    # reduce: resolution blow down factor
+    # leaf_size: Number of points at which to switch to brute-force, default=40
     def __init__(self, grd_lons, grd_lats, closeness_threshold=2000, reduce=1, leaf_size=40):
         if grd_lons.shape != grd_lats.shape:
             raise MyGenericException('incoming lons,lats must have same shape')